Re: [Groff] The future redux

[Peter Schaffter]

On Tue, Feb 25, 2014, Pierre-Jean wrote:
> But, to effectively use the paragraph at once adjustment, one
> need to patch the macro sets (or create some new ones).
> Because of the architecture of troff, things are done this
> way:
> - when troff format the paragraph at once, it also
>   deal with diversion (and footnotes) inside it. 
> - then it output the formated paragraph, and deal with
>   break page and traps.
> - The problem is that the diversion containing all the
>   footnotes of the paragraph has been populated when troff
>   encounters the traps and break page. So, footnotes might
>   not be on the correct page.
> 
> To handle these kind of situation, Heirloom Troff provide
> the \P[macro] escape sequence, which will execute 'macro'
> when the line is printed. So, to deal correctly with
> footnotes, the note macro *must* divert the content of each
> note inside a macro 'noteX', add the \P[noteX] to the
> content of the paragraph, and let the noteX macro do the
> usual job of a note macro.
> 
> I believe that Groff will face this kind of problems.

FWIW, the mom macros solved this thorny some time ago.  I won't
say it was easy--I still recall the hair-pulling six weeks I spent
getting it right.  And, to be honest, I'm not sure the mom solution
is 100% robust, though no one has ever reported a problem.  And,
again being honest, when I look at the macros these days, I'm not
certain even I can untangle all the hoops I had to jump through. :)


-- 
Peter Schaffter
http://www.schaffter.ca